Deep Dive — Postgres LISTEN NOTIFY Scales
You have probably used Postgres LISTEN and NOTIFY at some point. Maybe you used it for a chat system, or a progress bar, or a cache invalidation pattern. And maybe you assumed it would never scale past a few hundred concurrent connections. KraftyOne at DBOS ran the numbers and the results are surprising. Postgres LISTEN NOTIFY actually scales — and by scales I mean it handles tens of thousands of concurrent listeners without falling over. This matters for anyone building real-time event systems on a relational backend. If you have been reaching for Redis or a message queue as a workaround because you thought Postgres couldn't handle the load — this blog post is worth your time. The benchmark data is in the link. The short version: you may have one fewer moving parts in your architecture than you thought.